Physicists Nearer to a Key Clue to Universe

U.S. scientists released fresh data bolstering the case for the existence of the Higgs boson, a long-sought particle crucial to scientists' current understanding of how the universe is built.

The data, from the U.S. Department of Energy's Tevatron collider near Chicago, isn't enough on its own to confirm the existence of the Higgs particle. However, experimental results to be announced by European physicists on Wednesday will provide a stronger signal of where the Higgs is likely to be hiding.

Proof that the particle exists would help explain a big puzzle: why some objects in the universe—such as the quark, a constituent of protons—have mass, while other objects—such as photons, the constituent of light—possess only energy.

By extension, its discovery would help explain the presence of stars, planets and humans, and thus rank as one of the biggest coups for modern-day physics.

The officials at the European particle-physics laboratory CERN, meanwhile, are tight-lipped. "Whatever is announced on Wednesday will be interesting," said James Gillies, spokesman for the European lab. As to whether or not it might confirm the discovery of Higgs, "it's nature who will decide, not us," he added.

Because nobody knows what the mass of a Higgs boson might be, the particle must be hunted indirectly, typically in giant machines that propel particles to near-light speed, then smash them together and generate an array of other subatomic particles.

The search for Higgs got its biggest boost in December when researchers at the Large Hadron Collider, or LHC, near Geneva, Switzerland, said that data from two independent experiments had narrowed the range of the would-be particle's likely mass to between 124 and 126 gigaelectronvolts, or GeV. Those experiments were overseen by CERN.

Refined data from the LHC collisions, released in March, put the range between 122.5 and 127.5 GeV. And on Monday, data from the Tevatron collider indicated that the Higgs—if it exists—is consistent with a mass of 125 GeV.

"We have enough to get me excited that I'd be willing to bet your house it's real but not enough to bet my house," said particle physicist Rob Roser of Fermilab, which oversees the Tevatron collider.

Based on two experiments, the Fermilab team found that there is only a one-in-550 chance that the signal was a statistical fluke. That is why physicists are eagerly awaiting the CERN announcement Wednesday. This time, CERN will base its findings on roughly twice the amount of data available in December.